Put a screen behind the Espar heater to keep "stuff" from blocking or getting into the intake. I have an '07 RB50 floor plan so this might not concern others, but the way mine was set up, gear can very easily get into the return air intake on the heater. Here is a photo taken from the rear door looking into the storage area and you can see the heater intake.
There is a built in screen, but it won't stop bags, fabric and the like from getting sucked up against the intake.
This is a shot from the top thru the cabinet.
I just got a piece of 1/2" x 1/2" hardware cloth,
cut it to size and put a wood trim around it. I know, I know, it doesn't match but it's what I had. Can't see it unless you stick you head in there anyway....
Now I can stuff anything I want into this area and not worry about blocking the inlet. I did this mod because I had the problem. Makes a funny noise and the heater gets REAL hot.